1. Field of the Invention
The present invention is in the field of overvoltage arresters of the type in which electrodes are soldered into an insulator housing to provide a discharge gap between them. The electrodes are coated wtih a metallic activation compound at the confronting surfaces, the actvation layer including metallic barium aluminum and a matrix of metallic aluminum.
2. Description of the Prior Art
An overvoltage arrester of the type with which the present invention is concerned is disclosed in German Pat. No. 2619886. In that patent, there is disclosed an overvoltage arrester comprising an activation layer of barium aluminum and it was proposed that metallic titanium be introduced into the activator layer for stabilizing the response voltage at high current loads and for increasing the useful life while retaining unaltered electrical properties. It has been demonstrated, however, that a change in the response voltage occurs with a high number of switching events and with a high surge current load.